Abstract

                                Studios on the changes in the microbiological and chemical properties of red and black soils due to varying doses of gamma-irradiation indicated that complete eradication of micro- organisms was possible at 1500 kr and 2000 kr for rod and black soils, respectively: fungi were eliminated at 250kr to 1000 kr, actinomycetes at 1500kr and bacteria at 1000 to 2000kr indicating differential radio-sensitivity of the microbes present in the two soils. A marked decrease in organic carbon content, an increase in available N, marginal incr- ease in available P and a decrease in available K of both the soils due to gamme-radiation were recorded. The soil pH was lowered slightly in the red soil whereas no such change was observed in the black soil by the gamma-radiation. Autoclaving resulted in more significant changes in the above characteristics of both the soils than due to gamma radiation.

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